Disable the create button when the "Application folder" option is unchecked on Mac

Disable the create button when the "Application folder" option is unchecked on Mac

R=benwells@chromium.org,tapted@chromium.org
BUG=410767
Committed: https://crrev.com/4411faa68d1cf58b01af534dbcd3db75cacc55e3
Cr-Commit-Position: refs/heads/master@{#293755}

[wjywbs, 2014-09-06 23:33:36]

PTAL, thanks.

[tapted, 2014-09-07 23:54:06]

lgtm with nits

https://codereview.chromium.org/541913005/diff/1/chrome/browser/web_applicati...
File chrome/browser/web_applications/web_app_mac.mm (right):

https://codereview.chromium.org/541913005/diff/1/chrome/browser/web_applicati...
chrome/browser/web_applications/web_app_mac.mm:564:
withContinueButton:(NSButton*)continueButton;
nit: withContinueButton -> continueButton

https://codereview.chromium.org/541913005/diff/1/chrome/browser/web_applicati...
chrome/browser/web_applications/web_app_mac.mm:599: @end // @implementation
CrCreateAppShortcutCheckboxObserver
nit: remove comment - it's not typical to add it for new ObjC code

[wjywbs, 2014-09-08 02:36:56]

I updated the code. PTAL. Thanks.

[tapted, 2014-09-08 05:36:02]

slgtm

IMO, it's ready to check commit too, unless you want benwells to have a look
specifically. But it's likely he will just rubber-stamp it, which is redundant
with my lgtm.

[wjywbs, 2014-09-08 06:00:50]

The CQ bit was checked by wjywbs@gmail.com

[commit-bot: I haz the power, 2014-09-08 06:01:18]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/wjywbs@gmail.com/541913005/20001

[commit-bot: I haz the power, 2014-09-08 08:01:58]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-09-08 08:01:58]

Exceeded time limit waiting for builds to trigger.

[wjywbs, 2014-09-08 16:57:04]

The CQ bit was checked by wjywbs@gmail.com

[commit-bot: I haz the power, 2014-09-08 17:19:26]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/wjywbs@gmail.com/541913005/20001

[commit-bot: I haz the power, 2014-09-08 18:02:19]

Committed patchset #2 (id:20001) as 641630886cbccee73fd561167743072cf9ca8182

[commit-bot: I haz the power, 2014-09-10 03:47:12]

Patchset 2 (id:??) landed as
https://crrev.com/4411faa68d1cf58b01af534dbcd3db75cacc55e3
Cr-Commit-Position: refs/heads/master@{#293755}